private void SendMailCallback(IAsyncResult result)
{
try
{
_writer = _transport.EndSendMail(result);
// If some recipients failed but not others, send the e-mail anyway, but then return the
// "Non-fatal" exception reporting the failures. The sync code path does it this way.
// Fatal exceptions would have thrown above at transport.EndSendMail(...)
SendMailAsyncResult sendResult = (SendMailAsyncResult)result;
// Save these and throw them later in SendMessageCallback, after the message has sent.
_failedRecipientException = sendResult.GetFailedRecipientException();
}
catch (Exception e)
{
Complete(e, result);
return;
}
try
{
if (_cancelled)
{
Complete(null, result);
}
else
{
_message !.BeginSend(_writer, DeliveryMethod != SmtpDeliveryMethod.Network,
IsUnicodeSupported(), new AsyncCallback(SendMessageCallback), result.AsyncState !);
}
}
catch (Exception e)
{
Complete(e, result);
}
}
public void SendAsync(MailMessage message, object?userToken)
{
ObjectDisposedException.ThrowIf(_disposed, this);
try
{
if (InCall)
{
throw new InvalidOperationException(SR.net_inasync);
}
if (message == null)
{
throw new ArgumentNullException(nameof(message));
}
if (DeliveryMethod == SmtpDeliveryMethod.Network)
{
CheckHostAndPort();
}
_recipients = new MailAddressCollection();
if (message.From == null)
{
throw new InvalidOperationException(SR.SmtpFromRequired);
}
if (message.To != null)
{
foreach (MailAddress address in message.To)
{
_recipients.Add(address);
}
}
if (message.Bcc != null)
{
foreach (MailAddress address in message.Bcc)
{
_recipients.Add(address);
}
}
if (message.CC != null)
{
foreach (MailAddress address in message.CC)
{
_recipients.Add(address);
}
}
if (_recipients.Count == 0)
{
throw new InvalidOperationException(SR.SmtpRecipientRequired);
}
InCall = true;
_cancelled = false;
_message = message;
string?pickupDirectory = PickupDirectoryLocation;
CredentialCache?cache;
// Skip token capturing if no credentials are used or they don't include a default one.
// Also do capture the token if ICredential is not of CredentialCache type so we don't know what the exact credential response will be.
_transport.IdentityRequired = Credentials != null && (ReferenceEquals(Credentials, CredentialCache.DefaultNetworkCredentials) || (cache = Credentials as CredentialCache) == null || IsSystemNetworkCredentialInCache(cache));
_asyncOp = AsyncOperationManager.CreateOperation(userToken);
switch (DeliveryMethod)
{
case SmtpDeliveryMethod.PickupDirectoryFromIis:
throw new NotSupportedException(SR.SmtpGetIisPickupDirectoryNotSupported);
case SmtpDeliveryMethod.SpecifiedPickupDirectory:
{
if (EnableSsl)
{
throw new SmtpException(SR.SmtpPickupDirectoryDoesnotSupportSsl);
}
_writer = GetFileMailWriter(pickupDirectory);
bool allowUnicode = IsUnicodeSupported();
ValidateUnicodeRequirement(message, _recipients, allowUnicode);
message.Send(_writer, true, allowUnicode);
if (_writer != null)
{
_writer.Close();
}
AsyncCompletedEventArgs eventArgs = new AsyncCompletedEventArgs(null, false, _asyncOp.UserSuppliedState);
InCall = false;
_asyncOp.PostOperationCompleted(_onSendCompletedDelegate, eventArgs);
break;
}
case SmtpDeliveryMethod.Network:
default:
_operationCompletedResult = new ContextAwareResult(_transport.IdentityRequired, true, null, this, s_contextSafeCompleteCallback);
lock (_operationCompletedResult.StartPostingAsyncOp())
{
if (NetEventSource.Log.IsEnabled())
{
NetEventSource.Info(this, $"Calling BeginConnect. Transport: {_transport}");
}
_transport.BeginGetConnection(_operationCompletedResult, ConnectCallback, _operationCompletedResult, Host !, Port);
_operationCompletedResult.FinishPostingAsyncOp();
}
break;
}
}
catch (Exception e)
{
InCall = false;
if (NetEventSource.Log.IsEnabled())
{
NetEventSource.Error(this, e);
}
if (e is SmtpFailedRecipientException && !((SmtpFailedRecipientException)e).fatal)
{
throw;
}
Abort();
if (e is SecurityException ||
e is AuthenticationException ||
e is SmtpException)
{
throw;
}
throw new SmtpException(SR.SmtpSendMailFailure, e);
}
}
